Silicon nitride sintered body, rolling body with it, and bearing

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[Problem]Provide silicon nitride sintered bodies with good mechanical properties, particularly fracture toughness, and good product life when processed into products, rolling bodies using them, and bearings. [Solution] Silicon nitride sintered bodies contain rare earth elements and aluminum elements, the content of rare earth elements is 6% or more by weight% or 13% by weight in terms of oxides with respect to the total weight of silicon nitride sintered bodies, and the content of aluminum elements is 6% by weight% to 13% or less in terms of oxides, The inclusion (I) is present in the surface layer portion within 2 mm of the surface of the silicon nitride sintered body, and the ratio of the total cross-sectional area of inclusion (I) to the total cross-sectional area of the surface layer portion is 0.0 mm. 05% or more. [Selection Figure]Figure 1